Electrical connector



5 Sheets-Sheet 1 D. L. FF'ENDLER ELECTRICAL CONNECTOR INVENTOR. DONALD L. PFENEDLER Sept. 6, 196

Filed Nov. 2, 1961 ATTO EYE Sept. 6, 1966 D. L. PFENDLER 3,271,726

ELECTRICAL commcwon v Filed Nov. 2, 1961 5 Sheets-Sheet 2 90 FJ 6| f DONALD L. PFENDLER 64 24 27 ATTOR EYS Sept. 6, 1966 D. L. PFENDLEIR ELECTRICAL CONNECTOR 5 Sheets-Sheet 3 Filed Nov. 2, 1961 R E M R 0M TC! NDI W. l. D L A N O D ATTO NEYS United States Patent ()fiice 3,271,726 ELECTRICAL CONNECTOR Donald L. Pfendler, Sidney, N.Y., assignor to The Bendix Corporation, Sidney, N.Y., a corporation of Delaware Filed Nov. 2, 1961, Ser. No. 149,574 4- Claims. (Cl. 339-49) This invention relates to an electrical connector, and more particularly relates to a separable electrical connector.

The invention has among its objects the provision of a novel separable electrical connector which is particularly characterized by its simplicity and the ruggedness of its construction.

A further object of the invention lies in the provision of an improved separable electrical connector having novel means for securing the main par-ts of the connector together, such securing means being simple to operate and, in a preferred embodiment, being fully visible to the operator.

Another object of the invention is .the provision of a separable electrical connector of the type indicated, wherein the means for securing the parts of the connector together act to produce a force to draw the connector parts together which lies substantially along the common axis of the parts.

Still another object of the invention is the provision of a separable electrical connector with connector partsecuring means of a type indicated, wherein the partsecuring means selectively acts both to draw the parts of the connector together and thrust them apart so that they are at least substantially disengaged.

Still further objects of the invention, in a preferred embodiment thereof, lie in the provision of the separable electrical connector wherein the correct angular disposition of the part-securing means can be ascertained by visual and tactile inspection before the parts of the connector are initially engaged, and wherein the separable electrical connector is particularly characterized by the ease and speed with which the parts of the connector may be selectively m-atingly engaged and disengaged from each other.

Another object of the invention lies in the provision of a method of cross-connecting a plurality of electrical conductors.

Let another object of the invention lies in the provision of an improved separable multiple wire electrical connector, of the type wherein one connector part may be, in its connecting portion, the exact counterpart of the connecting portion of a cooperating connector part.

A further object of the invention lies in the provision, in a connector of the type indicated immediately above, of improved means for electrically connecting together corresponding contacts in at least one of the connector parts.

The above and further objects and novel features of the invention will more fully appear from the following description when the same is read in connection with the accompanying drawings. It is to be expressly understood, however, that the drawings are for the purpose of illustration only, and are not inteneded as a definition of the limits of the invention.

In the drawings, wherein like reference characters refer to like parts throughout the several views,

FIG. 1 is a view in longitudinal axial section through the two parts of a preferred embodiment of connector in accordance with the invention, the two parts of the connector being shown separated and in position to be engaged, the cables and conductors which are normally connected to the contacts of the respective connector 3,Z7i,726 Patented Sept. 6, 1966 parts being omitted, certain of the parts being shown in elevation;

FIG. 2 is a view in side elevation of the connector parts of FIG. 1 assembled in fully engaged mating condition;

FIG. 3 is a view in end elevation of the connector part shown at the right in FIG. 1, the view being taken from the line 33 of FIG. 1;

FIG. 4 is a view in end elevation of the part of the connector shown at the left in FIG. 1, the view being taken from line 44 of FIG. 1;

FIG. 5 is a fragmentary view in axial section through the connector of FIG. 1 with the parts thereof in fully engaged mating position;

FIG. 6 is an exploded view in perspective of the boards making up each of the circuit board assemblies 33 and 33' of the connector parts in accordance with the illustrated embodiment of the invention;

FIG. 7 is an enlarged fragmentary view in side elevation of one of the printed circuit boards making up the assembly 38; and

FIG. 8 is a view partially in elevation and partially in section of a circuit board assembly made firom the boards of FIG. 6, a stem portion 30 of a contact being shown in position to be introduced into the circuit board assembly.

The preferred embodiment of connector in accordance with the invention illustrated herein is designated as a whole by the reference character 10. Such connector is composed of two main parts, the part at the right in FIG. 1 being designated 11 and the part at the left being designated 12. Connector part 1 1 includes a rear tubular body 14, to the left or front end of which is secured a casing or shell 15 of the connector part proper. Casing 15 is generally circular cylindrical in shape and lies coaxial of element 14. Parts 14 and 15 are secured together by a rear thickened end portion 16 of body 15, which abuts a shoulder 17 of an annular seat on the front end portion of element 14. A short axially directed sleeve 19, which projects forwardly within part 16 of element 15, has an annular groove therein within which is positioned a resilient ring 21 which functions to seal elements 14 and 15 together. Such elements are secured together by a plurality of machine screws 20 (one shown) angularly spaced about connector part 1 1. Such machine screws extend through passages in the flanged forward end of element 14 and are threaded into bores in the rear end portion 16 of element 15, as shown.

Mounted within shell 15 is a composite electrically insulating insert 22 which supports and locates a plurality of electrical contacts spaced over its area. The connector shown is of the so-called hermaphrodite type, wherein one portion of the insert bears socket contacts and the other portion of the insert bears pin contacts. In the embodiment shown in FIG. 1 the lower part 24 of the forward portion of insert 22 is axially longer than the upper portion 25 thereof, the two parts being of substantially equal area, part 24 being bounded by a flat surface 26 which lies along the diametral axial plane of connector part 11. Portion 24 of the insert carries a plurality of socket contacts 27, whereas portion 25 carries a plurality of pin contacts 29. Each of the contacts has a solder well or other connecting means at its rear end portion 30, whereby it may be connected to its respective one of the conductors which extend forwardly through the rear end of body 14 and into the space 31 within such body.

The rear of body 14 is provided with a cable gripping and sealing means, generally designated 32, which includes a forward annular wedge block 35, a rear annular wedge block 36, and an annular rubber-like grommet member 34 which is interposed between blocks 35 and 36, member 34 surrounding the cable that passes therethrough. Member 34 may be compressed into sealing contact with the outer surface of the cable by means of a hollow internal nut 37 which has screw threaded connection with the rear end of body 14. Nut 37 also serves to secure the forward end of a conventional cable embracing and gripping means 39, as shown.

The forward ends of contacts 27 and 29 are shielded by an axially split hood which is fixedly secured to the shell of connector part 11. Such split hood has a portion 40, which shields contacts 27, of smaller diameter, portion 40 being secured to shell 15 by means of a ring 38 at the rear end of such shell portion, ring 38 being brazed to shell 15 and abutting a transverse shoulder formed on the latter. The rear end portion of hood 40 overlies the forward portion 41 of shell 15 as shown. The upper larger hood portion 43, which shields contacts 29, is retained on shell 15 by means of a ring 42 which is integral with hood 43 and which is press fitted over the ring 38 on the rear of hood 40. The rear end body portion of hood 43 lies radially spaced from the outer surface of portion 41 of shell 15 to provide a space 53 therebetween'. The forward end of shell 15 is provided with an annular seat within which is secured a resilient sealing ring 44 which cooperates with a similar sealing means on the shell of connector part 12 to seal the two shells together when the parts are matingly engaged as shown in FIG. 5.

Rotatably mounted upon shell 15 and coaxial therewith is a coupling sleeve 45. Sleeve 45 is secured to shell 15 so as to be held from any substantial axial movement with respect thereto. Such connection is provided by an annular flange 47 on the rear of shell 15, such flange being rotatably received between a shoulder 46 of an annular seat in sleeve 45 and a spring ring 49 which is snapped into an annular seat on the sleeve rearwardly of flange 47.

The main extent of coupling sleeve 45 has a circular cylindrical inner surface which closely confronts the outer surface of the rear portion of hood 43 and which is separated from the rear portion of hood 40 by a space 50 projecting forwardly in an axial direction. The forward end of coupling sleeve 45 is provided with a plurality of connector part fastening means 51 which are disposed equally angularly about the axis of the sleeve. In the embodiment shown, two such fastening means 51, positioned diametrically opposite each other on the sleeve 45, are employed. Each of fastening means 51 is made up of an axially forwardly extending arm 52 which projects from the forward outer edge of the main body portion of sleeve 45, the arm 52 having a radially inwardly directed lug 54 afiixed to its outer end. Lugs 54, as will appear hereinafter, are adapted to be received within generally helically directed grooves on a fixed portion of the housing of the mating connector part, whereby to secure the two parts of the connector together.

In the preferred embodiment of connector shown, each of the connector parts is provided with securing means similar to the above-described means 51, and each of the connector parts is provided with grooves which receive the lugs of the connecting means of the mating connector part. As shown in FIGS. 2 and 3, connector part 11 has two oppositely disposed generally helical grooves in the outer surface of sleeve 45. Each of such grooves has a forward or entry end 56 which is disposed immediately adjacent and clockwise of a connector means 51 as connector part 11 is shown in FIG. 3. As shown in FIGS. 2 and 4, connector part 12 has two oppositely disposed generally helical grooves in the outer surface of sleeve 71. Each of such grooves has a forward or entry end 82 which is disposed immediately adjacent and clockwise of a connector means 77 as connector part 12 is shown in FIG. 4.

Connector part 12 has an annular casing or shell 57 within which is secured an electrically insulating insert 59. Insert 59 has an axially shorter portion 60 within which are mounted a plurality of contact pins 64, and an axially longer portion 61 within which are mounted a plurality of socket contacts 65. Portion 61 of the insert has a generally diametrally extending bounding surface 62. The configurations of the inserts of connector parts 11 and 12, and the spacing of the contacts mounted therein are such that the inserts and contacts interfit in the manner shown in FIG. 5 when the connector parts are matingly engaged. Fixedly connected to shell 57 is a first, smaller hood portion 66 which shields part 61 of insert 59, and a second, larger hood portion 69 which shields portion 60 of the insert. Hood portion 66 is attached to shell 57 by means of a ring 67 brazed to the rear end of the hood portion; the larger hood portion 69 is secured to ring 67 by means of a ring portion 70 press fitted over ring 67. The diameters of the hood portions of the two connector parts are such that when the connector parts are matingly engaged as shown in FIG. 5 the hood portions snugly telescope within each other as shown and form, in effect, two protective rings about the mating contacts, such rings being incomplete only in the narrow zones produced by the axial slots 48 between the confronting edge portions of hoods '40 and 43 of connector part 11 and the slots 68 between the confronting edges of hood portions 66 and 69 of connector part 12.

When it is desired to disconnect the connector parts, the sleeve 45 is turned in the reverse direction. Because such sleeve is fixed against substantial axial movement with respect to shell 15, such reverse turning of the sleeve causes the two connector parts to be positively thrust or jacked apart to a point at which the formerly mated pin and socket contacts are removed or substantially removed from engagement with each other, and will allow the two connector parts to be completely separated by purely axial movement with respect to each other. Rearwardly of insert 59 in connector part 12 there is positioned a grommet 74 by means of which the conduct-ors leading to the various contacts in such connector part may be sealed to shell 57. The seal is provided by a grommet-compressing ring 75 which is thrust axially into the position shown in FIG. 1 by a bushing 76 which has threaded engagement with a rear end of shell 57.

Fixedly connected to the shell 57 of connector part 12 is an outer sleeve 71 which lies coaxial therewith. The connection between sleeve 71 and the shell is effected by brazing the rear end of the sleeve to the ring 70 of hood portion 69. integrally connected to sleeve 71 and projecting from the forward edge thereof are two diametrically opposed locking means 77 in the form of arms 79 having radially inwardly directed lugs 80 at their forward free ends. Locking means 77 are similar to the abovedescribed locking means 5 on sleeve 45. Two generally helical grooves 81 of opposite hand from grooves 55 are disposed in diametrically opposite rela tionship on sleeve 71. The lug-entering ends 82 of grooves 81 are positioned alongside and closely adjacent each adjoining arm 79, as shown.

In effecting connection between the parts 11 and 12, such parts are aligned as shown in FIG. 1 .and are turned about their axes so that the pin contacts on the one connector part lie opposite the socket contacts on the other connector part. The connector parts are then advanced toward each other so that the hoods 40 and 69 on the one hand and 43 and 66 on the other begin to telescope. The sleeve 45 may not be turned, if this has not already done, so that the lugs 54 of securing means 51 thereon enter ends 82 of grooves 81 on connector part 12. At the same time, the lugs 80 of connector part 12 will enter ends 56 of bayonet grooves 55 on connector part 11.

Counterclockwise rotation of sleeve 45, FIG. 3, will then cause the lugs to advance into the respective cooperating grooves so as to draw the connector parts 11 and 12 into fully engaged mating relationship. The diametral surfaces 26 and 62 of the respective inserts, and the confronting edge portions of the split hoods on the respective connector parts insures the correct alignment of the contacts which are to be mated. The disposition of the entering ends of the bayonet grooves immediately alongside the adjoining arms of the connecting means facilitates the initial location of the two connector parts with respect to each other upon such initial engagement. The bayonet grooves 55 and 81 are of such length that when the connector parts are connected in fully mated position, each arm 52 will have been turned from substantial engagement with one of the arms 79 to at least substantial engagement with the other of such arms 79. Consequently, it can readily be told both by visual and tactile inspection whether or not the connector parts have been fully mated.

Each of connector parts 11 and 12 in the embodiment shown is provided with a protective cap which may be placed thereon when the connector parts are disengaged. Cap 84 for connector part 11 is tethered thereto by means of a ring 85 which is secured to body 14 by bushing 37. A flexible cord or wire 36 extends from ring 85 to cap 84, the flexible member 86 being attached to the cap by a rivet 90 which also serves to connect external and internal hood portions 87 and 89, respectively, of cap 84 together in coaxial relationship. Cap 84 is provided with connecting or fastening means, which may be in the form of bayonet grooves similar to those above described which are provided on sleeve 71.

The cap for connector part 12 is generally designated 91. Such cap is tethered to the shell of connector part 12 by a fitting 92, secured to flange 72, and by a flexible wire or cord 94 extending from the fitting to the cap. Member 94 is secured to cap 91 by a rivet 97, which also serves to connect together outer and inner portions 95 and 96, respectively, of cap 91.

Cap 91 is provided with connecting means in the form of arms "and lugs and bayonet grooves similar to those disposed on sleeve 51 of connector part 11. Such parts of cap 91 are therefore designated by the same reference characters as those used in connection with connector part 11 but with an added prime.

In the illustrative separable electrical connector of the invention, the mating portions of the connector parts are identical. This permits connect-or part 11 to be mated with any connector part similar to part 11, and connector part 12 to be mated with any connector part similar to part 12. Separable electrical connectors of such type are particularly useful in the field, since any connector part of an electrical system so equipped may be mated with any other connector part of the system.

Although each of the connector parts 11 and 12 is shown as being provided with connecting means including both arms and lugs and bayonet grooves receiving such lugs, one connector part of the connector pair may .have connecting means consisting only of either arms and lugs on the one hand or grooves on the other. Such modified connector parts will still mate with a connector part which has only grooves or arms and lugs, respectively, such connecting means still providing adequate securing of the connector parts together. Thus, for example, connector part 12 may be provided only with bayonet grooves, and connector part 11 may be provided only with anns and lugs. The same is true of protective caps 84 and 91, which may be provided only with securing means which mates with the securing means on the connector part with which the cap is associated.

In the illustrative separable connector, each contact pin in each connector part 11 and 12 is cross connected to a corresponding socket contact in such part. As a result, circuit continuity is preserved Whenever each connector part is mated with a d-itferent, similar connector part of the same type. Thus in the illustrative example, cross connection is made between the contact pins 29 and the socket contacts 27 of connector part 11, and cross connection is made between pins 64 and socket contacts 65 of connector part 12 by means 33 and 33, respectively, to be described. It is to be understood, however, that in some instances it is not necessary to provide a cross connecting means in one connector part. Thus, for example, if in connector part 12 only the socket contacts or pin contacts are to be employed in the circuit, no cross connecting means 33' is necessary.

The cross connecting means of connector part 11, generally designated 33, is particularly shown in final assembled condition in FIG. 8, and in the process of assembly, wherein the parts thereof are designated generally by the reference character 28, in FIG. 6. Cross connecting means 33 is in the form of an assembly of six printed circuit boards 99-104, inclusive, and an end stiffening board 98. The body of each of such boards is made of stiff electrically insulating material such as epoxy resin impregnated glass fiber sheet known as Panelyte grade 1644 sold by the St. Regis Paper Company. The circuit boards 99-104, inclusive, are substantially thinner than board 98; thus, for example, boards 99-104, inclusive, may each have a thickness on the order of .005, whereas stiffening board 98 may have a thickness on the order of .0625. Each of circuit boards 99-104, inclusive, bears pairs of electrical terminals which are symmetrical about a vertical central plane as the boards are shown in FIG. 6, whereby electrically to connect the contact pins in the respective vertical rows on one side of the connect-or part to the corresponding socket contacts on the other side of the connector part. The terminals and the connecting strips therebetween on each of circuit boards 99-104, inclusive, are so arranged as to be spaced from and electrically insulated from the terminals and strips connecting the various other different rows of contacts. Thus in FIG. 6 there are shown for illustration six parallel lines which represent the axes of the rear stem portions 30 of socket or pin contacts which are to extend through the cross conecting means 33. It will be seen that each of such lines intersects a respective one of circuit boards 99-104, inclusive, at a terminal of a printed circuit element thereon, but that such line passes through the others of boards 99-104, inclusive, at locations substantially spaced from the terminals and the cross connecting elements of the printed circuits thereon.

Each of circuit boards 99-104, inclusive, has the same construction and is similarly made, except for the configuration of the printed circuit elements thereon. Accordingly, it will sufiice to describe the manner of preparation of circuit board 99. Board 99 may be initially supplied with a thin layer of copper completely covering one board face thereof. A disc is cut from such copper coated board, is accurately machined to the proper diameter, and has the holes indicated in FIG. 6, punched or drilled therein. Such holes are to receive the stems 30 of those contacts which are not to be electrically connected to the printed circuit elements to be formed upon disc 99. Such printed circuit elements, generally designated 105, are formed in accordance with conventional printed circuit practice: Thus a resist coating is printed upon the copper coated face of the disc in the locations of the printed circuit elements 105, following which the board 99 is submitted to the action of an acid to etch away all of the copper coating except that which underlies the resist-coated areas. The resist coating is then removed from the disc so as to leave the circuit elements exposed.

The circuit elements 105 have generally rounded terminal portions 106 connected by narrower intermediate port-ions. In forming the circuit board fragmentarily shown in FIG. 7, the terminal portions 106 are cleaned and fiuxed, following which a solder ball 107 is applied to each terminal portion 106. For clarity of illustration, the thickness of the printed circuit elements 105, including the terminal portions 106 thereof, has been exaggerated in FIG. 7; this is also true of the thickness of solder balls 107. In the actual construction of the circuit board 99, the combined thicknesses of terminals 106 and solder balls 107 is much less than the thickness of the board 99 itself, so that when the circuit boards 99-104, inclusive, are superimposed and pressed together, the protruberance formed by terminals 106 and solder balls 107 become imbedded in the next adjacent circuit board and so that the various layers of the composite connecting means 33 lie substantially flat and parallel, as shown in FIG. 8.

In making the assembly 33 of FIG. 8, the six circuit boards 99-104, inclusive, are coated on their broad confronting faces With a suitable adhesive such as that known W as Hysol 12-007, sold by the Hysol Corporation of Clean, New York. The thus coated circuit plates are assembled in a suitable fixture which assures registration ofcorresponding holes through the plates and thus the proper location of the printed circuit elements on the various plates with respect to each other. A somewhat thicker board 98 having holes therein aligned with all the holes formed or to be formed in plates 99404, inclusive, is assembled on top of plate 99 after one or more of the confronting faces of plates 98 and 99 have been adhesively coated with Hysol. The thus described assembly is then subjected to a satisfactory laminating cycle which with the illustrative adhesive may include subjection of the assembly to a laminating pressure of 1,000 pounds per square inch for minutes While the assembly is held at a temperature of 200 F. Following this, the disc is removed from the laminating fixture and is cooled from its temperature of 200 F. to ambient temperature in a period of approximately 1 hour and 40 minutes.

The assembly 33 is then completed by drilling holes completely therethrough along the axis of each of the terminals of the respective circuit elements, and by countersinking the entry end of each of such holes 109 in plate 98. The completed circuit element 33 is now assembled with the other elements of connector part 11 as follows: The contact pins 29 and the contact sockets 27 are thrust rearwardly into the insert 24, 25 so that the stem portions of such contacts extend rearwardly of the insert as shown in FIG. 1. The composite connecting element 33 is now mounted upon the insert and the stem 30 of the contacts, the reinforcing plate 98 being positioned as first to receive the free ends of the stems 30 as indicated in FIG. 8. Electrical connection is now made between each of stems 30 and the respective terminal of the printed circuit element through which it passes. Such connection may be made by heating the outer ends of stems 30 of the contacts for a suflicient time to allow the heat to run along the stems 30 so as to fuse the solder ball on the printed circuit terminal through which the stem extends, thus to form a soldered connection between the terminal and the stem. Such heating may be effected by means such as an electrically heated soldering iron applied sequentially to the stems 30, or all of such stems may be heated at once as by suspending the recited assembly of contacts, insert, and composite connecting means 33 above a bath of molten material into which the free ends of the stems 30 extend, such molten material being at a temperature substantially above the melting point of the solder balls 107.

Following the making of such assembly, the insert 24, \2-5 with the contacts and connecting means 33- may be -inserted in shell 41 by being thrust in a direction from right to left with respect thereto. A grommet-like thick layer 110 of electrically insulating material is then applied within shell 15 rearwardly of connecting means 33. Material 110 may be, for example, polyurethane applied by potting technique. An electrically insulating preformed wafer 111 having holes therein to receive the outer ends of stems 30 of the contacts is then applied over the potting compound 110. Following this, the potting compound is cured by being subjected to elevated temperature for the requisite time.

It can-be seen that the use of the novel composite connecting means 33 in connector part 11 and a similar composite connecting means 3-3 in connector part 12 produces a much more compact and reliable connector than is possible by the use of conventional jump wires between corresponding pin and socket contacts. The connector parts are sold in finished condition, there rernainin-g only the task of connecting the proper circuit wires to the outer ends of the stems 30 of the pin or socket contacts of each connector part. In some instances it may be desirable to terminate the end-s of stems 30 of those contacts Whichare not to be directly connected 7. r

to circuit wires somewhat to the left (FIG. 1) of insulating wafer '111, whereby the possibility of misconnecting circuit wires and contacts is greatly reduced.

Although only one embodiment of the invention has been illustrated in the accompanying drawings and a limited number of embodiments has been described in the foregoing specification, it is to be especially understood that various changes, such as in the relative dimensions of the parts, materials used, and the like, as well as the suggested manner of use of the apparatus of the invention, may be made therein without departing from the spirit and scope of the invention as will now be apparent to those skilled in the art.

What is claimed is:

1. In an electrical connecting device, a laminated stack of thin discs of electrical insulation cemented together, said stack having a plurality of openings therethrough, electrically conductive printed circuit elements applied to surfaces of said discs, each said element having a terminal portion adjacent each of at least two of said openings and being segregated firom the other said openings by the cemented together disc surfaces adjacent there to, a metallic contact extending through each said opening in sliding engagement with the walls thereof, solder means, applied to said elements before lamination of said stack and fused after the insertion of said contacts into said openings, for electrically connecting each said contact to only one of said printed circuit elements between any two adjacent discs, and a resilient contact supporting member having openings mating wit-h the openings in said stack for receiving said contacts, said contacts having interlocking relation with said supporting member within the openings in the latter.

2. A multiple contact electrical connecting device comprising a tubular shell, a unitary resilient contact supporting insert mounted in said shell, a plurality of elongated metallic contacts extending through said insert and having interlocking engagement therewith, a laminated stack of discs of insulating material cemented together in said shell adjacent said insert and having openings therethrough for receiving the ends of said contacts proectrng from said insert, printed circuit elements on said drscs and interposed between adjacent discs, and solder means connecting each said contact to one of said elements whereby each of said contacts is electrically connected to at least another of said contacts.

3. The method of making a mulitple contact electrical connecting device which comprises applying printed circuit elements to the surfiaces of a plurality of discs of electrical insulating material, applying at least two spaced spots of solder on each said element, stacking said discs and adhesively securing adjacent surfaces thereof together to thereby segregate and embed said elements, forming openings through the stack of discs, each said opening intersecting at least one of said elements and a spot of solder thereon, mounting metal contacts in parallel spaced relation in a supporting member mateable with said stack and simultaneously extending all the mounted contacts through said openings in sliding engagement with the walls 9 10 of the latter, applying heat to the projecting portions of 2,247,386 7/1941 John 339-89 said contacts to fuse said spot-s of solder, and allowing 2,384,267 9/1945 Andersen 339-49 the contacts and solder to cool, whereby each said con- 2,386,117 10/ 1945 Andersen 339-49 tact is electrically connected by the solder to a said printed 2,409,650 10/ 1946 Wiggins 285-316 circuit element within said stack. 5 2,502,291 3/ 1950 Taylor 339-17 X 4. A method as defined in claim 3 which includes 2,513,080 6/1950 Burtt 339-89 mounting said contacts in parallel spaced relation in a 2,700,140 l/ 1955 Phillips 339-94 supporting member mateable with said stack and extend- 2,877,441 "3/ 1959 Narozny 339-17 X ing all the mounted contacts simultaneously through said 2,898,522 8/1959 H anden 339-17 X Openings. 10 2,958,064 10/1960 Swengel 339-17 2,987,691 6/1961 Ross 339-49 References Cited by the Examiner 3,036,188 4/1963 ROSS 33949 UNITED STATES PATENTS BOBBY R AY P E 2,014,853 9/1935 Ley et al 339-94 X G xamme" 2,124,207 7/1938 Neesen 339 49 PATRICK C O Examiner- 

1. IN AN ELECTRICAL CONNECTING DEVICE, A LAMINATED STACK OF THIN DISCS OF ELECTRICAL INSULATION CEMENTED TOGETHER, SAID STACK HAVING A PLURALITY OF OPENINGS THERETHROUGH, ELECTRICALLY CONDUCTIVE PRINTED CIRCUIT, ELEMENTS APPLIED TO SURFACES OF SAID DISCS, EACH SAID ELEMENT HAVING A TERMINAL PORTION ADJACENT EACH OF AT LEAST TWO OF SAID OPENINGS AND BEING SEGREGATED FROM THE OTHER SAID OPENINGS BY THE CEMENTED TOGETHER DISC SURFACES ADJACENT THERETO, A METALLIC CONTACT EXTENDING THROUGH EACH SAID OPENING A SLIDING ENGAGEMENT WITH THE WALLS THEREOF, SOLDER MEANS, APPLIED TO SAID ELEMENTS BEFORE LAMINATION OF SAID 